Power miter saws are routinely found in woodworking environments for use in various cutting applications, such as bias cutting of long, but narrow stock. Over the past several years, the use of the miter saw has expanded significantly due largely to versatility, accuracy, cost and simplicity of use. Today, miter saws are commonly found in commercial wood working shops, home shops and even in retail outlets in the place of radial arm and table saws.
A typical power miter saw includes a relatively compact horizontal flat top work surface measuring about two feet in length having a vertically projecting backstop, commonly referred to as a fence. The material to be cut, such as a wood, plastic, metal, ceramic, masonry or similar materials is horizontally supported by the work surface and vertically aligned along the fence. A rotary blade and associated motor are pivotally mounted to, and above, the work surface to plunge cut into a stationary workpiece and thereby accurately forming a cut to separate the workpiece at a specified dimension. Some miter saws are referred to as “sliding miter saws” because they are pulled to the front of the work table in the raised position, lowered, and then pushed towards the fence while cutting through the workpiece.
While the power miter saw, also referred to as a “chop” saw, is an efficient and proven power cutting tool, there remain a number of shortcomings associated with the operation thereof. One such problem with the miter saw operation relates to the precise and repeatable measuring of the cut length, specifically as it relates to a relatively short workpiece. Previously, a table saw was utilized wherein a movable rip fence and/or miter guide would position the workpiece based on a pre-determined dimension. While this problem has been widely recognized for many years by the users, miter saw manufactures have failed to develop an effective measuring and securing means for use with these saws, especially when a short piece length is required.
Miter saws are designed and manufactured according to the American National Standards Institute (ANSI) and Underwriter's Laboratories Inc. (UL) standards contained in ANSI/UL 987, Stationary and Fixed Electric Tools. Miter saws are required by this standard to have the necessary blade guards to mitigate the potential for hand and finger injuries. Despite these standards there remains an ongoing risk of serious injury inherent with conventional miter saw designs. In 2005 alone the US Product Safety Commission reported 29,779 miter saw injuries requiring a trip to a hospital emergency room. (NIESS code 832 & 895)
In response to the problem associated with accurately controlling the cut length of a workpiece, U.S. Pat. No. 5,845,555, MULTI-POSITION ADJUSTABLE WORK STOP ASSEMBLY, was issued to Dawley the inventor to the present application. Other solutions are suggested in U.S. Pat. No. 6,899,006 issued to Jolkovski and in U.S. Pat. No. 6,557,601 issued to Taylor, where a linear scale provides a reference stop for a substantially long workpiece. However, in all of the noted patents, the fence and motor, as well as the associated blade guard, potentially interfere when short pieces are to be safely cut.
Therefore, a serious problem remains with the use of miter saws in relation to operator safety—particularly when executing a cut on a relatively short piece. The potential for injury is further increased when angled or miter cuts are being made on short pieces. More particularly, during normal use the rotating saw blade often comes in close proximity to the operator's hands and fingers as the rotating blade plunges down into the workpiece. As a result individuals have been seriously injured by inadvertent contact with the saw blade while operating the miter saw. When cutting relatively short pieces the risk of injury is increased since the operator is now required to position and support a workpiece against the fence in close proximity to the blade while cutting. If the cut-off piece is not held in some manner there is also the risk of the piece becoming a projectile once the cut is completed.
Several devices are intended to protect operators from injury while operating miter saws, including blade guards and electric brakes, which serve to limit hand contact with the rotating blade. Blade guards and brakes, however, have proven ineffective because the blade becomes exposed when cutting and moving at up to 8,000 RPM (275 MPH) while the operator is attempting to secure the workpiece within inches of the blade. Other attempts to improve safety features include providing a workpiece securing member designed to assist the operator in mechanically mounting the work in a “hands free” manner. U.S. Pat. No. 4,283,977, issued to Baton, and U.S. Pat. No. 6,422,115, issued to Shibata, disclose mechanisms adapted for clamping the workpiece during the sawing process, so as to keep the operator's hands free from the danger area of the saw. These devices, however, are adapted for securing a relatively long workpiece within the cutting area, and are generally not usable when a relatively short cut-off is required.
Again, the blade guard and motor interfere with a securing device, which limits the clamp's proximity to the blade, especially since a miter saw is capable of rotating at least +/−45 degree about the axis perpendicular to a work surface. As discussed above, this limits the applicability of such clamps for use with smaller workpieces, which must be secured much closer to the saw blade path. Hence, a need exists for improvements directed to protecting operators from injury by securing a relatively short workpiece during the cutting operation.
Further, as noted above, a need also exists for a securing mechanism that is capable of adequately controlling and indexing the cut-off length in order to provide greater accuracy, but more importantly to provide adequate safety for an operator.
In accordance with the present invention there is provided a safety apparatus for securely holding a workpiece, comprising: a work surface; and a securing member operable in cooperation with, and pivotally attached to, said work surface, said securing member securing the workpiece while operated on by a cutting tool.
In accordance with one aspect of the invention, there is provided A workpiece stop and securing apparatus for positioning and securely holding a workpiece in relation to a saw blade, comprising: an adjustable mount movably attached to a fence, said adjustable mount including a stop member attached thereto in order to control a distance between the saw blade and the stop member; and a workpiece securing member pivotally attached to said adjustable mount, in a plane generally parallel to a work surface, to apply a holding force to a surface of the workpiece.
In accordance with yet another aspect of the invention, there is disclosed a method for cutting a short piece from a workpiece, comprising: attaching an adjustable mount to a work surface of a power tool; pivotally attaching a workpiece stop, including a securing member, to the mount; setting and locking the mount to position to provide a workpiece stop at a defined distance from a cutting tool; abutting an end of the workpiece to the stop member; applying a force against a surface of the workpiece with the pivotally attached securing member; energizing the power tool; and engaging the cutting portion of the power tool at the specified workpiece cut-off length, while continuing to grasp the workpiece with the securing member in a securing orientation.
These and other advantages and features, which characterize the invention, are pointed out with particularity in the drawings as described within the following embodiments of the invention.
The present invention will be described in connection with various embodiments, however, it will be understood that there is no intent to limit the invention to the embodiment described. On the contrary, the intent is to cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.